Glucose with sodium ethoxide

There have been few investigations of the reactions of polyhydroxy compounds with alkali metal alkoxides in nonaqueous media at room temperature.. Percival" reported the preparation of D-glucose-NaOEt and D-glucose NaOMe by treating d-glucose with sodium ethoxide, and penta-O-acetyl-D-glucopyranose with sodium methoxide, respectively. The adducts were dried under vacuum at 60° for 24 hours, a treatment which would make the presence of any significant proportion of alcohol of solvation unlikely. Any traces of moisture in the preparative medium preclude the formation of an aJkoxide adduct. 

Toluenesulphonamido)phenyl] ethyl 2,3,4-tri-(9-benzyl-Q -D-gluco-pyranoside has been condensed with 2,3,4-tri-0-benzyl-6-0-(7V-phenyl-carbamoyl)-l-0-tosyl-D-glucopyranose to yield 2,4-(4-toluene-sulphonamido)-phenyl ethyl 2,3,4,2, 3 4 -hexa-0-benzyl-6 -<9-(7V-phenylcarbamoyl)-a-isomalto-side. The disaccharide was decarbanilated in ethanol with sodium ethoxide. The sequence of coupling with the 1-O-tosyl-D-glucose derivative followed by decarbanilation was repeated to form the tri- and tetra-saccharide derivatives. 

Azoxy compounds can be obtained from nitro compounds with certain reducing agents, notably sodium arsenite, sodium ethoxide, NaTeH, NaBH4—PhTeTePh, and glucose. The most probable mechanism with most reagents is that one molecule of nitro compound is reduced to a nitroso compound and another to a hydroxylamine 119-42), and these combine (12-51). The combination step is rapid compared to the reduction process. Nitroso compounds can be reduced to azoxy compounds with triethyl phosphite or triphenylphosphine or with an alkaline aqueous solution of an alcohol. ... 

The presence of three hydroxyl groups per glucose unit was shown by the preparation of a triacetate and a tribenzoate. Six or seven methyla-tions (using dimethyl sulfate and concentrated alkali) of dextran did not raise the methoxyl content above 41% (theoretical maximum 45.6%). Also, Purdie methylations (using methyl iodide and silver oxide) and methylation with thallium ethoxide and methyl iodide were ineffective in raising the methoxyl content of methylated dextran above 43.5%. The maximum theoretical methoxyl content was eventually attained by modified Muskat methylations. 6 Partially methylated dextran suspended in anisole solution was treated with sodium in liquid ammonia, and the sodium salt of methylated dextran thus formed was allowed to react with methyl iodide. The methoxyl content of the partially methylated dextran was raised by three such methylations from 42% to 45.5% and by five such methylations from 30% to 45.4%. 

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